teleimg: allow underscores and hyphens in file id

Change-Id: I6f6cdd3a13cdbed41f57c40ac1b2e46c4707be32
diff --git a/personal/q3k/teleimg/main.go b/personal/q3k/teleimg/main.go
index 85cce31..5c5e280 100644
--- a/personal/q3k/teleimg/main.go
+++ b/personal/q3k/teleimg/main.go
@@ -23,7 +23,7 @@
 var (
 	flagPublicListen  string
 	flagTelegramToken string
-	reTelegram        = regexp.MustCompile(`/fileid/([a-zA-Z0-9']+).([a-z0-9]+)`)
+	reTelegram        = regexp.MustCompile(`/fileid/([a-zA-Z0-9_-]+).([a-z0-9]+)`)
 )
 
 type server struct {